Virtual reality (VR) has been described as a new and unique type of learning media primarily because it encourages active participation. However, a large number of VR worlds are barely more than passive 3D graphic visualisations. This might be due to the lack of guidelines for the design of interactive worlds, or to the learning preferences of the designers themselves. The literature indicates a number of principles, especially in the area of VR design and learning theory that could form the basis of appropriate design guidelines and this thesis presents these as a set of guidelines for VR designers. There is a lack of information about the learning preferences of VR designers or the design of appropriate help systems for VR learning media so four additional fieldwork studies were carried out to investigate the learning styles, communication styles, attitudes towards the use of VR in learning and training situations, and preferences for the design and use of VR help systems using a sample of VR designers and VR design students. The results indicated that the learning style and communication profiles of VR designers may not be suitable for the design of active learning material. It was also found that VR designers had positive attitudes towards the development of VR in general but less so for learning situations. VR designers tended to provide mainly text-based (visual) instruction in their designs, which may be linked to their predominantly visual learning modalities. However, the results suggested that visual-dominant VR design students were equally likely to prefer voiced (auditory) instructions when used naturally within a VR world. The findings from these four studies were incorporated into a broad set of top-level guidelines that form the first step towards a general model for the design of active, participatory VR learning environments.